[PATCH v2 2/3] arm64/efi: efistub: cover entire static mem footprint in PE/COFF .text
From: mark.rutland@arm.com (Mark Rutland)
Date: 2014-08-14 11:31:25
Also in:
linux-efi
On Wed, Jul 30, 2014 at 11:59:03AM +0100, Ard Biesheuvel wrote:
The static memory footprint of a kernel Image at boot is larger than the Image file itself. Things like .bss data and initial page tables are allocated statically but populated dynamically so their content is not contained in the Image file. However, if EFI (or GRUB) has loaded the Image at precisely the desired offset of base of DRAM + TEXT_OFFSET, the Image will be booted in place, and we have to make sure that the allocation done by the PE/COFF loader is large enough. Fix this by growing the PE/COFF .text section to cover the entire static memory footprint. The part of the section that is not covered by the payload will be zero initialised by the PE/COFF loader. Signed-off-by: Ard Biesheuvel <redacted> Acked-by: Mark Salter <redacted>
This looks sane to me and it seems we do the same for x86 as of c7fb93ec51d4 (x86/efi: Include a .bss section within the PE/COFF headers). So: Acked-by: Mark Rutland <mark.rutland@arm.com>
quoted hunk ↗ jump to hunk
--- arch/arm64/kernel/head.S | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 144f10567f82..b6ca95aee348 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S@@ -151,7 +151,7 @@ optional_header: .short 0x20b // PE32+ format .byte 0x02 // MajorLinkerVersion .byte 0x14 // MinorLinkerVersion - .long _edata - stext // SizeOfCode + .long _end - stext // SizeOfCode .long 0 // SizeOfInitializedData .long 0 // SizeOfUninitializedData .long efi_stub_entry - efi_head // AddressOfEntryPoint@@ -169,7 +169,7 @@ extra_header_fields: .short 0 // MinorSubsystemVersion .long 0 // Win32VersionValue - .long _edata - efi_head // SizeOfImage + .long _end - efi_head // SizeOfImage // Everything before the kernel image is considered part of the header .long stext - efi_head // SizeOfHeaders@@ -216,7 +216,7 @@ section_table: .byte 0 .byte 0 .byte 0 // end of 0 padding of section name - .long _edata - stext // VirtualSize + .long _end - stext // VirtualSize .long stext - efi_head // VirtualAddress .long _edata - stext // SizeOfRawData .long stext - efi_head // PointerToRawData-- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo at vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html